Assessment of the curving performance of heavy haul trains under braking conditions

To study the curving performance of trains, 1D and 3D dynamic models of trains were built using nu- merical methods. The 1D model was composed of 210 simple wagons, each allowed only longitudinal motion; whereas the 3D model included three complicated wagons for which longitudinal, lateral, and vertical degrees of freedom were considered. Combined with the calculated results from the 1D model under braking conditions, the behavior of draft gears and brake shoes were added to the 3D model. The assessment of the curving performance of trains was focused on making comparisons between idling and braking conditions. The results indicated the following： when a train brakes on a curved track, the wheel-rail lateral force and derailment factor are greater than under idling conditions. Because the yawing movement of the wheelset is limited by brake shoes, the zone of wheel contact along the wheel tread is wider than under idling conditions. Furthermore, as the curvature becomes tighter, the traction ratio shows a nonlinear increasing trend, whether under idling or braking conditions. By increasing the brake shoe pressure, train steering becomes more difficult.

Application Research of Music Therapy in Mental Health of Special Children

A healthy psychological state is the premise for children to carry out various activities.Previous surveys have shown that children with special needs are affected by their own obstacles and are more prone to psychological problems such as sensitivity,low self-esteem,and impulsiveness.Therefore,it is necessary to provide more sys-tematic mental health education support for special children.Mental health education programs are an efficient form of maintaining children’s mental health.However,in thefield of special education,the number of mental health education courses developed according to the physical and mental characteristics and developmental needs of special children is relatively small,and there are many difficulties in the implementation process.Autism dis-order(ASD)is a kind of pervasive developmental dysfunction that is relatively common and representative in clinical practice.In recent years,the number of autistic children has continued to surge,and has gradually expanded from a family problem to a serious social problem.At present,the evaluation of the effect of autism intervention mainly relies on various behavioral scales,which are subjective to a certain extent.At the same time,due to the unclear pathogenesis of autism,the treatment of autism cannot be predicated on the right medicine,and can only be intervened in various ways.The purpose of this paper is to explore the difference between the EEG signals of autistic children and typically developing control(TD)children through the analysis method of EEG signals,and based on the analysis of EEG signals from an objective point of view,to study whether the music therapy method of Chinese Zither playing training can effectively Improving the brain functional status of chil-dren with autism yields positive therapeutic outcomes.The experimental results show that the complexity of brain electrical signals of ASD children is much lower than that of TD children,and there is a significant difference in the brain functional state between the two.The music therapy method based on Chinese zither playing training can improve the brain function of autistic patients,and there is a positive therapeutic effect.And with the exten-sion of the training period,the effect may be more significant.Chinese zither playing training can provide a new direction for the intervention of autism.

Technical Feasibility Study of Passenger Rail Service along the West Route between Las Vegas and Los Angeles

The study evaluates the feasibility of running passenger train service from Las Vegas, NV on the Union Pacific Railroad (UPRR), to Barstow, on the Burlington Northern Santa Fe (BNSF) track, to Mojave on UPRR track again, and to Lancaster connecting Metrolink to their destinations in Southern California. In this study, the railroad infrastructure was inventoried and issues related to running the passenger service were identified. Passenger train operation was evaluated based on the Rail Traffic Controller (RTC) simulation model. The performance measures of passenger trains including travel time, overall delay and average speed are analyzed. The uncertainty in freight flow and its impact on providing the passenger service is addressed by conducting a sensitivity analysis. The conclusion is that the existing railroad infrastructure is sufficient to provide a passenger train service from Las Vegas to Los Angeles. From an operational perspective, the passenger train is not expected to influence freight trains’ performance on the existing railroads. When freight train flows are increased to 50%, the influence of passenger train service on the freight operation is still minimal. This study recommends restoring a platform at the Las Vegas Station. At the Mojave Station, special care should be given on running the passenger trains where there is no direct railroad connection from BNSF to UPRR. Platforms and walkways require construction at the Lancaster Station for transferring passengers between the Metrolink trains and X-Train. Transferring the passenger train at this station involves stopping the train on mainline and coordinating the operations between different railroads.

Exploration of key traction-running equipment and its problems on heavy-haul trains and research on technology development

In recent years,heavy-haul train technology has seen a number of innovations worldwide,and train traction-running technology has also made great progress,resulting in a rich pool of experience and a range of promising applications.This paper summarizes the key technologies of traction running in heavy-haul combined trains,especially locomotive and rolling-stock technology,traction technology,braking technology,control technology,communication technology and safety technology.At the same time,based on an analysis of practical applications,this paper further explores the main problems and urgent needs of traction equipment on heavy-haul trains.With an eye to the future,the heavy-haul railway system will develop in the direction of informatization,automation and intelligence,in order to build a greener,more energy-saving,safer and more efficient railway.This paper therefore looks forward to the technical developments of heavy-haul combined trains,and provides a reference for the development of heavy-haul railways.